In a vehicle having a large rear space such as a minivan, it is proposed to perform air-conditioning operation for the rear space independently from a front space. An air conditioning apparatus for a vehicle rear space is for example disclosed in Japanese Unexamined Patent Document No. JP-A-10-109523.
In the air-conditioning apparatus, as shown in FIG. 9, a blower fan 901 is arranged in a blower case 909 in a form of scroll and is rotated by a blower motor 910, which is driven by a power from a vehicle-mounted battery. The blower fan 901 sucks an inside air inside of a passenger compartment through a suction port 908 and blows the air into a cooler case 914, which is provided at a position downstream of the blower case 909. In the cooler case 914, an evaporator 902 performs heat exchange between a refrigerant flowing therein and the air blown by the blower fan 901, thereby cooling the air. A heater case 915 is connected to a downstream position of the cooler case 914. In the heater case 915, a heater core 904 is provided on a side adjacent to the passenger compartment and an air mix door 903 is provided on a side adjacent to the outside of the vehicle. The heater core 904 performs heat exchange between an engine cooling water and the cooled air having passed through the evaporator 902, thereby heating the air. The air mix door 903 can be moved to an optional position (air mix mode) between a position (MAX HOT) where the air is entirely introduced toward the heater core 904 and a position (MAX COOL) where the air is entirely introduced toward a cooled air bypass passage.
Further, in the heater case 915, an air mix chamber 911 is formed at a position downstream of the bypass passage and the heater core 904. Thus, the heated air passed through the heater core 904 and the cooled air passed through the bypass passage merge with each other in the air mix chamber 911. The mixed air is distributed toward a roof opening 906 and a foot opening 907 by a mode door 905. The mode door 905 is selectively set to a roof air-blowing mode position, a foot air-blowing mode position, or a bi-level mode position. In the roof air-blowing mode, the air is entirely introduced toward the roof opening 906. In the foot air-blowing mode, the air is entirely introduced toward the foot opening 907. In the bi-level mode, the mode door 905 is set to an optional position between the roof air-blowing mode position and the foot air-blowing mode position so that the mixed air is divided toward the roof opening 906 and the foot opening 907 with a desired ratio. Here, the blower unit 909, the cooler case 914, and the heater case 915 are located in a space between a side trim 912 and an outer panel 913 that defines an outer wall of a body.
Because the space of the air mix chamber 911 is reduced to improve mountability of the air conditioning apparatus to the rear space of the vehicle, the heated air passed through the heater core 904 is forcibly directed toward the air mix chamber 911 by a guide 916. Therefore, it is likely to be difficult to maintain the volumes of air blown from the respective air-blowing outlets sufficiently. On the other hand, the space between the side trim 912 and the outer panel 913 is limited. Therefore, it is required to further improve the mountability of the vehicle rear seat air conditioning apparatus. Further, in the bi-level mode, it is required to control air temperature such that the air blown toward a passenger's foot area is hotter than the air blown toward a passenger's face area.